Why Expecting Parents Need To Double Check Any Genetic Testing They Do In Utero

Genetics is fascinating stuff — how else would you know that Grandpa’s partying habits might actually be linked to your kid’s long-term health? Unfortunately, there’s increasing evidence that the hypothetical scenarios in some genetics studies can lead to medical misdiagnosis that result in catastrophic decisions by doctors and expecting parents.

According to a recent feature in The Atlantic, more and more unborn babies are being given incorrect diagnoses for rare genetic diseases when doctors take cues from weak evidence suggested in scientific literature. One study-about-a-study from the National Center for Genome Resources found that a quarter of mutations (different variants found in your kid’s DNA), which were previously linked to childhood genetic disease, turned out to be more common and less serious than some papers had suggested. Another study from Massachusetts General Hospital found that in a sample of over 60,000 people, each showed 53 mutations classified as ‘disease-causing’ according to two big scientific databases; but when researchers took a closer look at 200 mutations, only 9 actually qualified as pathogenic.

When psychology or social science papers with junk results are circulated, the worst case scenario for parents is often some time being wasted. But with clinical genetics, expecting parents and doctors might make life-altering, in utero decisions about things like abortions or surgical implants for babies based on an oversimplified understanding of recent research.

The worst part about this trend is that so much of clinical genetics leads to useful diagnoses that save lives. So, rather than assume cutting edge diagnosis are based on junk science, experts recommend that expecting parents press their prenatal doctors to cross-check genetic variants on sites like ExAc Consortium to see how common or rare they actually are. Meanwhile, it’s on scientific journals to get more stringent about what gets published.

And you can and should hew to the age-old maxim: don’t believe everything you read.